Printing-machine.



No. 643,372. Patented Feb. I3, I900.

G. R. CORNWALL.

PRINTING MACHINE.

(Applicati m filed Dec. 30, 1898.)

(No Model.)

whewea TH: uo'RFus PETERS c .ilnrrnn STATES PATENT @FFIGE.

GEORGE R. CORNIVALL, OF MOUNT VERNON, NEW YORK.

PRINTING- MACHINE.

SPECIFICATION forming part of Letters Patent No. 643,372, dated February 13, 1900.

' Application filed December 30,1898. Serial No. 700,744. (No model.)

To all whom it may concern.-

Be it known that I, GEORGE R. CORNWALL, a citizen of the United States, residing at Mount Vernon, Westchester county, State of New York, have invented certain new and useful Improvements in Printing-Machines, of which the following is a specification.

This invention relates to a method of removing water from the surface of a printingplate and from the inking system on machines that are operated on a lithographic or surface principle. Some of the difficulties in surface or lithographic printing have been due to the fact that the inking-rollers lick up moisture from the plate until finally these rollers instead of carrying on their surface an even film of ink get covered over with a mixture of ink and water, causing the design to spread in printing and results in a lack of luster and sharpness of the impression. In surfaceprinting the dampening-rollers first pass over the plate, depositing a film of moisture on all non-printing portions of the plate. Vt hen the inking-rollers pass over the plate, the film of moisture prevents their depositing any ink on the moisture-covered parts of the plate, they giving ink to the design-carrying portion of the plate only. In this operation the inking-rollers wipe off most of this moisture from the non-printing part of the plate, as well as giving ink to the design-carryingportions. This moisture mixes with the ink on these rollers and their riders and distributers. A portion of the moisture is necessarily left upon the non-printing portion of the plate, enough, at any rate, to make it a little damp, and in consequence when brought in contact with paper coated with kaolin the plate pulls this coating from the surface of the paper. This sticking to the surface of the printingplate at the next revolution of the press takes ink from the inking-rollers and deposits it on the next sheet of paper printed.

The object of my invention is twofoldfirst, to remove the moisture gathered by the inking-rollers and their riders and distributors; second, to dry the plate after each inking just before the plate is brought into impression with the surface to be printed upon. The method that I propose using for this is to blow or draw, just before the impression and after the inking of the design, over the surface of the plate a blast or draft of air, and I also arrange to have similar currents of air traverse the inking-rollers-that is to say, the form-rollers, their riders and distributers, or any portion thereof. This air may be either air in the ordinary atmospheric condition or, better, air that has been dried by either pass ing through or over a desiccating agent or through heated pipes or a heated chamber. The air may be either at the atmospheric temperature or heated. Warm dry air would take up with greater avidity the moisture which is my object to remove. I may also instead of forcing the air against these surfaces to be dried reverse the operation and suck the moisture from the surface by a suction-blast.

The advantage of my invention is that it enables the machine to print sharper and stronger work, while allowing the machine to be simplified in several respects. For exampic, I can dispense with some of the inking rollers and with the inking-slab. These were heretofore necessary to Wipe out the moisture gathered by the ink on the inking-rollers and on the plate. As the ink-slab occupies a large portion of the surface of the form-cylinder it is obvious that by omitting it the form-cylinder can be considerably reduced in diameter, thus giving a sharper impression while printing at a slower peripheral speed. Also as practically the entire form-cylinder can be utilized for the printing-plate it makes it possible to have a nearly continuous printing design, and in consequence this press can print.

upon a web or roll of paper. p

The drying of the plate after the inking and before the impression prevents the paper getting damp and stretching and the consequent throwing out of register in printing. Having the plate dried also makes it possible to print upon papers faced with the various coatings common to the papers used by type-printers, which could not heretofore be used by surfaceprinters, as the coated surface coming in contact with the damp plate is pulled off.

Referring to the accompanying drawing, I show a diagrammatic side elevation of the principal elements of a rotary printing-press with my invention applied thereto.

1 represent-s the form-cylinder, having the printing-plate 2 secured thereon in the usual IOO manner. The said plate, however, in this case may occupy nearly the entire circumference of the form-cylinder, as shown.

The impression-cylinder 3, inking-rollers 4, 5, and 6, and water-rollers 9 may be arranged in the usual manner, as shown. A pipe 10 has branches 11 extending in proximity to the inking-rollers 4, 5, and 6, and has also a branch or branches 12 extending in proximity to the form-cylinder 1. A fan or blower 13 is connected, through a heater 14 and a chamber 15, containing a desiccating agent, to the pipe 10 and its branches 1'1 12. These branches have openings 16,facing the inking-rollers and the form-cylinder, respectively, so that the air which is forced by fan 13 through pipe 10 blows from these openings over the surface of the inking-rollers and also over the surface of the printing-plate, so that the surfaces of all the elements are traversed by currents of air, tending to remove the moisture from same,

this eifect being aided by the heating and drying of this air. It will be noticed that the branch pipe or pipes 12, which apply the airblast to the printing-plate on the form-cylinder, are located between the inking-rollers and the impression-point, (indicated at 00,) so that the drying effect is only exerted on the printing-plate between the times of inking and printing. 7

Thus the successive operations performed by the press are, first, moistening by the water-rollers; second, inking by the inking-rollers; third, drying off superfluous moisture by the air-blast; fourth, impression.

The pipe branches 11 are shown insuch position that the air-currents supplied thereby will extend over all the inking-rollers namely, the form-rollers 4, the riders 5, and the distributors 6; but, if desired, these pipes may be adapted to blow upon only a portion of such inking s'ystemfor example, upon the form-rollers only.

Instead of blowing the air through the pipes 10 11 12 onto the surface to be dried I may exhaust the air through said pipes by a reverse motion of the fan, and thus draw the moisture out of the ink on the surfaces referred to. The current of air applied to the plate may thus be a blast or a suction current.

Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is

1. In a printing-machine, the combination with the printing-surfacecarrying means, the inking devices and the water-applying devices, of means for removing water from the inking devices.

2. Ina printing-machine, the combination with the means for carrying the printing-surface, of the inking-rollers and means for applying currents of drying air to the inkingrollers.

In a printing-machine the combination with the means for carrying the printing-surface, of the inking-rollers and means for ap plying currents of drying air to said printingsurface and inking-rollers.

4. In a printing-machine, the combination with the inking devices, of means for supplying a current of drying air to such devices.

5. In a printing-machine, the combination with the prin ting-surface-carrying means, of means for applying water to such printingsurface, devices for applying ink to such printing-surface, and means for applying a current of drying air to such ink-applying devices, to dry the same, substantially as and for the purpose set forth. I

6. In a printing-machine, the combination with the means for carrying the prihting-surface, the inking-rollers, and the water-rollers, of a pipe having an opening in proximity to the inking-rollers and means for establishing a current of air through such pipe.

7. In a printing-machine, the combination with the printing-surface-carryin g device and the inking devices, of a blower-and-pipe connection for applying a current of air to the inking devices, and a heater interposed in such pipe connection.

8. In a'printing-machine, the combination with the printing-surface-carrying device and the inking devices, a blower-and-pipe connection for applying a current of air to the inking devices, and a chamber containing'a desiccating agent interposed in such pipe connection.

9. In a printing-1nachine, the combination with the means for carrying the printimq-sui-- face, of the inking means, blower-and-pipe connections for applying drying'air to the inking means and the printing-surface, and heating means interposed in such pipe connections.

10. In aprinting-machine, the combination with the means for carrying the printing-surface, of the inking means, blower-a'nd-pipe connections for applying drying air to the inking means and the printing-surface and a chamber containing a desiccating agent interposed in such pipe-connections.

GEORGE E. OORNWVALL.

Witnesses ARTHUR P. KNIGHT, M. V. Brnooon. 

